theraindog writes "Errata are not uncommon with new processors, but a problem with the TLB logic in AMD's quad-core Opteron and Phenom processors appears to be quite serious. The erratum is so severe that AMD has issued a 'stop ship' order on all quad-core Opterons. AMD has also blamed this bug for the delay of the 2.4GHz Phenom, despite the fact that the erratum is unrelated to clock speed. A BIOS-based workaround for the issue has been made available to motherboard makers, but it apparently carries a 10-20% performance penalty. What's more disturbing is that AMD knew of the erratum and the potential performance hit associated with fixing it before it launched the Phenom processor. Hardware provided to the press for reviews did not include the fix, conveniently overstating Phenom performance."Slashdot | Erratum Plagues Quad-Core Opterons, Phenoms

I am really Hoping that AMD catches with there Processor just so there is more competition out then it should bring down the prices of Quads even further

Aren't TLBs used for virtual memory? Is the performance issue as apparent when the CPU has enough RAM (8GB or more) that virtual memory isn't needed?
Or maybe AMD's implementation of the TLB in their marchitecture requires a TLB lookup for any memory operations.